of carlinville



o. w. CORR, or CARLINVILLE, 1Lr.n\1o1s.`` 1

STEAM-VALVE.

specication of Letters Patent No. 26,480, ated December 2o, i859. ,I

t Steam-Engines; and I do hereby declare that the following is a full, clear, andeXact description of the same,.reference being had to the accompanying drawings, forming part ofthis specification, in which-` Figure l, is a plan of a steam chest with its cover removed to show the valve,y Fig.`

2, is a face view of the valve. Fig. 3, is a central section of the steam chest, valve and passages, in the plane indicated by line m, w, of Fig. l. Fig. 4, is a central section of the same in the plane indicated by the line y, y,

y 0f Fig. 1.

l radial, the distance between the margins 71 Similar letters of reference indicate corresponding parts in the several figures.

To enable others skilled in the art to make and use my invention I will proceed to describe its construction and operation.

A, is the steam chest of circular form, receiving the steam through a pipeB.` C, is the valve seat also of circular form containing two steam ports a, a', arranged in opposite positions relatively to the center of the seat and a central exhaust port Z9, which communicates with a side passage y'.

D, is the valve consisting of a plate of the form of a circle having an opening c, el, e, whose sides c, el, are radial to the center said opening being for the admission of steam to the ports 0;, a, alternately, being made to occup-y a greater or less ortion of the circumference of the circle o the valve according as `the steam is intended to be admitted to the cylinder ofthe engine during a greater or less portion of the stroke of the piston. In the face of the said valve there is a cavity f, g, 71 z', of which the margin f, ranges with the margin of the exhaust port b, the margin g, with the outer margins of the steam ports, and the margins 71 i, are

and z', being equal to a semicircle minus the width of one of the steam ports a, a, so that the valve in making one revolution for every revolution of the engine may malntain a a rotating driving shaft F, `whichworks u free communication between each steamport alternately and thehexhaust port, duringa complete half revolution` of1 the `engine" and hence during the complete strokeof the pisj ton. The distance between the marginslc, It, of the valve is equalfto the :width of :either of the ports a, a', andzthemargins c, andi/i', are inline so that thevalverevolving inthe s l direction of the arrow shown upon inl` 1,1 Figs. 2, and 3,1may` open either port a, orffi);` a', to the exhaust at the precise moment that y, it opens the other. to the steam.` y 1 y E, is the stem ofthe valve `having aheadf@` I Q k, which is received :in al slotlin the `end` of through a stufling box` in the backof the"`" steam chest.` This Stemhas cut" upon ita screw thread l, which `passes through `but fits rather tightly in a `female screw threadpro-` vided in thecenter ofthe valve, andthe in` y Il ner end of the said stem enters a cavity in a bridge piecem, extending across theexhaust po-rt b, and rests upon the end of a `screw u, screwing into` the bridgeIn case ofthe t, valve being caused by the pressure of steam r l, on its back to produce` more than a cert-ain degree of friction upon` its seat, the stem will turn within the female screw thread andlso slightly withdrawfthevalveand relieve itof," l the excessive friction. 1 f 1 t s y s r I do not claim` tobe the ,first inventor of r a rotary valve servingfor the induction, cut-y` j ting-olf and eduction of the steam in astearn l engine, but l r y 3 l I D `1 l What I claim as my invention and desire y to secure by Letters Patent j l l. Providingthe extremityof theiriving` l shaft F, within the steam chest with aslot Q to receive the head Ic, of thevalve ste1n,a`nd t permit the self' adjustment of 1l said, headf90 within the slot, as setlforth.

2. The arrangementyof` the screw threads upon the valve andthe valve `stem substantially as shown, so that thevalve `will adjust l s itself if the frictiongbecomes too great, as l A. MGKIM Dunois,

FREEMAN. 

